Acid regression stage of sludge digestion at a temperature 21C extends over a period of______________?
Found an error? Read our corrections policy and submit a sourced correction below. You can also share a useful explanation in your own words.
A. 30 days
C. 60 days
D. 15 days
Found an error? Read our corrections policy and submit a sourced correction below. You can also share a useful explanation in your own words.